The invention is concerned with rotary railroad car couplers, especially a rotary F-type coupler which employs an AAR Standard F-type coupler head as shown, for example, in U.S. Pat. No. 2,973,105 which is directed to a rotary F coupler whose shank is pinned to a rotary connector which, in turn, is mounted within the yoke for rotation about the coupler axis.
The tremendous growth in the size of railroad cars in the past decade has placed severe strains on railroad car coupler assemblies, including the car coupler, striker, yoke and draft gear. Moreover, railroad beds in disrepair cause misalignment of the trackway which produces undesirable movement between adjacent railroad cars thereby creating heretofore unknown fatigue failures in components of the car coupler assemblies. The invention is directed to increasing the size of the essential components of a rotary F car coupler assembly to meet these increasing stresses which the assemblies are being subjected.
Briefly stated, the invention is in a rotary railroad car F coupler assembly which is mounted within a standard carsill housing that has a generally rectangular cross-section configuration and is secured to the underside of a railroad car. A yoke, disposed in the housing, is provided with a longitudinally extending cylindrical opening. A wearplate is positioned between the top of the yoke, closest the railroad car, and the adjacent underside of the housing. A connector is mounted in the opening of the yoke for rotation about the longitudinal axis of the yoke. The connector is provided with a pair of aligned pinholes which extend laterally from an opening which extends longitudinally through the connector. A car coupler, including a coupler head that protrudes from the yoke and a shank which extends from the head in the direction of the yoke and terminates at a butt end which extends through the opening of the rotary connector into seating engagement against an adjacent front follower which is spring loaded by the draft gear mechanism, is pinned to the connector for unitary rotation. A cover plate is secured to the underside of the housing in spaced relation from the car to close the housing and help support the yoke.
The size of the rotary connector and the coupler shank, adjacent the pinhole in the shank, are substantially increased by using a pair of twin, parallel wearplates between the top of the yoke and adjacent underside of the housing. The twin wearplates are spaced a sufficient distance apart so that a top ridged portion of the yoke, closest the railroad car, can be expanded upwardly between the wearplates closer the housing, so that the diameter and consequent cross-sectional area of the cylindrical opening of the yoke can be substantially increased, without radically changing the overall size of the yoke so that it won't fit into the standard carsill housing. The rotary connector and the butt end of the coupler shank are enlarged accordingly, to provide a larger yoke and connector which are undiminished in strength, and a coupler shank whose strength in the area of the pinhole is greatly enhanced, so that the coupler is less susceptible to fracturing and breakage.